基于CCD传感器的球罐焊接机器人焊缝跟踪

CCD Sensor Assisted Weld Seam Tracing Method for Spherical Tank Welding Robot

主要研究以轮式移动机器人为本体的球罐焊接机器人的焊缝跟踪问题。轮式移动机器人本体难以实现实时、准确的运动轨迹控制 ,而球罐焊接工艺要求焊炬必须精确地沿焊缝以恒定的焊接速度焊接。为解决这一矛盾 ,本文首先设计了在一定运动约束条件下的轮式机器人本体与焊炬运动机构 ,建立了基于双CCD传感器的焊缝路径检测系统。在对轮式移动机器人在球罐表面移动时的运动学分析基础上 ,建立了机器人本体在一定误差范围内跟踪焊缝的控制模型 ,并设计了相应的控制策略。根据机器人与焊炬之间的运动约束关系 ,提出了焊炬位置实时精确的跟踪控制策略。现场工艺试验表明 ,所研制的球罐焊接机器人焊炬跟踪精度可达± 0 .5mm 。

This research is mainly addressed on solving the weld seam tracing problems existing in design of wheel-mobile-robot based spherical tank welding robot. Generally, the moving route of wheel-mobile-robot can not be controlled accurately in real-time, however, weld tomb must precisely moves along the weld seam at given speed to guarantee the weld quality of spherical tank. To solve this conflict, the moving mechanical structure of wheel-mobile-robot and weld torch, which is under certain constraint condition, has been designed. A weld seam route detecting system based on two CCD sensors has been established. After the dynamic analysis about the motion of wheel-mobile-robot on spherical tank, a control model for wend seam tracing of wheel-mobile-robot and its control strategy have been developed. Then, according to the constraint relations between the motions of wheel-mobile-robot and weld torch, a control algorithm which could control the weld torch position accurately in real time has been put forward. Th e exploited spherical tank welding robot has high weld torch tracing accuracy (up to ±0.5 mm), and has been successfully applied in the automatic manufacturing of spherical tank.